It is easy to break the interlock switch by putting the cover back on from the
back. Always spread the cover slightly and put it on straight down from the TOP.
After investing in two sets of high grade offset screwdrivers (and cutting down
one Phillips bit), I was able to replace the 422 interlock switch without
moving the transformer; I took off the 3 most accessible circuit board screws,
loosened by ¼” the most distant one, loosened the transformer screw connections
from the board, and lifted the board up in the area of the switch. There was
room for detailed careful work
I epoxied 2 blind 2-56 nuts to the bottom of the board to mount the new switch,
thus making it easily removable when everything is put together.
Also I made 2 new, doubled up flexible longer solder connection insulated
wires to the switch from the board so that, once the switch is removed next
time there is room to unsolder it and solder in a new one without the heat
loosening the wire connection to the circuit board.
I used 2-56 hex-head cap screws to mount the new switch, and 4-40 hex head cap
screws for 2 of the circuit board screws to make it easier to use Allen
wrenches should they need to be removed.
I ended up using a slightly different OMRON switch than the original as you
can see in the picture, almost the same part number but with shorter and
narrower terminals with holes in them to allow for the new leads. The original
switch could be used by clipping the NC contact off and shortening the two
other contacts.
Mike
K4QET
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|